As the lead sweeper for his platoon during a four-month stretch in Afghanistan, the 24-year-old Camp Pendleton-based Marine went on 40 mounted and dismounted combat patrols over a 212-mile route with the sole responsibility of finding improvised explosive devices.

One wrong step could have resulted in death or dismemberment, so imagine the stress when the enemy started firing at Munoz on top of it.

Munoz went into his first deployment in March with scant experience in the field. But after coming home in July, he was awarded the Navy and Marine Corps Achievement Medal with Valor for his superior performance with 1st Platoon, Weapons Company, 2nd Battalion, 5th Marines, Regimental Combat Team 6.

During his time in Afghanistan, Munoz identified, properly marked and informed his chain of command of eight IEDs, a 100 percent find rate. His work ensured that every Marine in his platoon made it home.

“Maybe part of it was luck. I don’t doubt that,” Munoz said. “But I did my job. I was told I was going to be sweeper. Some people have bad luck. Do your job well, do it right and you should be fine. That’s what we’re taught.”

Munoz was put to the test almost immediately.

On March 23, just nine days into his first deployment, Munoz and his platoon encountered enemy machine-gun fire while on a reconnaissance patrol through Now Zad District. While sweeping a wadi — a dry river bed that fills up when it rains — Munoz was initially pinned down but continued to sweep for IEDs once adjacent vehicles provided suppressive fire.

As the firefight continued, according to an official account of events, Munoz located and marked three IEDs. Nobody in his platoon was hurt that day, not even from the enemy gunfire.

“In general, sweeping for mines is a little scary because one wrong step and you can blow up,” Munoz said. Getting shot at “increases everything 10-fold. It’s stressful enough sweeping.

“When we heard the gunshots, I was like, ‘Aah crap. Now I’ve got to worry about that!’ ”

Two weeks later, Munoz again encountered enemy fire while sweeping for IEDs.

“He again, and with disregard for his own safety, continued to sweep and locate an improvised explosive device in the road under suppressive fires from the other dismounts and the vehicles before embarking his vehicle,” according to a Marine Corps account of events. “His complete disregard on multiple occasions for his own safety and steadfastness in the performance of his duty ensured his platoon had continuing success throughout combat operations.”

And there’s more to being the lead sweeper than just finding IEDs. Munoz was responsible for $400,000 worth of government equipment that is used to detect the potentially lethal devices.

Even with that, Munoz identified a shortfall of equipment and led a fundraising effort among his platoon to purchase more. He said he pitched in $100 of his own money and did not ask to be reimbursed.

Upon returning home, the Los Angeles native said he was surprised to win such a prestigious honor.

“Everyone told me ‘you deserve it,’ so I might as well take it,” he said. “I did my job, my platoon did theirs. Everybody did their part, and we had a successful deployment.”